In Ansys Fracture Mechanic, How tweaking the parameters (like increasing/reducing the length) of Major, Minor & Contour radius of the crack affects the J-integral? How each elements mentioned above affects the J-integral individually?
2. And what the value of J-integral means here? If the J-integral value is higher, does it means that it needs high energy for the propagation of crack?
For linear elastic fracture mechanics (LEFM) J-integral is equivalent to the Energy Release rate (G). Higher the J (or G), tougher is the material, i.e. it requires higher energy for crack initiation (not propagation) for a stationary crack.
For LEFM, G (and so J also) is related to Stress intensity factor (SIF) K as J=G= K^2/E, where E is the Young's modulus. And yes, K/G/J surely depends on parameters like length of the crack, root radius (notch radius) of the crack.
Another important point, which should be mentioned is that for very large notch radius, you will get some J out of FEM calculation, but that may not be equivalent to K, because SIF is defined only for sharp crack and not the blunt one.
I hope this helps you.
just to add..higher J menas that crarck prapogation is difficult..possibly due to large plasticity around the crack which is absorbing lot of input mechanical energy....
Thank you all for your response! I highly appreciate! Can anyone who answered or following can suggest me a journal or a thesis paper regarding J-integral? And possibly it's relationship with Crack? Because I want to dig deeper in this area for my thesis.
Hi,
I think any basic book on fracture mechanics will tell you the relationship between crack geometry and SIF (K) or G. And because J is related to these parameters J will also depend upon crack geometry. Some of the books are mentioned. I have also mentioned a paper on J-integral by Rice, probably that may help you.
https://www.crcpress.com/Fracture-Mechanics-Fundamentals-and-Applications-Third-Edition/Anderson-Anderson/9780849316562
http://www.springer.com/us/book/9781402028632
http://www.springer.com/gb/book/9783642192395
Article A path independent integral and the approximate analysis of ...
- Badges
- Science topic